Loosen the oil filter cover to allow engine oil to drain back into the oil pan, then raise the car and secure it on jack stands. Remove the splash shield and front end reinforcement plate from under the engine, and proceed to drain the engine oil. Disconnect the electrical harness connector at the oil level sensor and remove the lower oil pan mounting bolts. If the lower pan does not separate easily from the upper pan, tap lightly with a rubber mallet to break it free, avoiding the use of prying tools. Check the tightness of the oil pump mounting bolts and the oil pump chain sprocket nut. When installing the oil pan, thoroughly clean all old gasket material from mating surfaces and use a new gasket. Install threaded guide studs at marked locations to assist in positioning the new oil pan gasket and oil pan, preventing damage to the sealing lip. Install new oil pan mounting bolts with threads coated in sealer, then remove the guide studs and install the remaining oil pan bolts. Reassembly follows the reverse order of disassembly, ensuring the oil filter cover is tightened. Follow the correct installation procedure for the front end reinforcement, and after adding engine oil, start the engine and raise the speed to 2,500 rpm until the oil pressure warning light goes out, which should take about 5 seconds.